box b1 5 5 10
box b2 5 0 0 5 5 5
box b3 0 5 0 5 5 5

makeconnected r b1 b2 b3
checknbshapes r -wire 18 -face 18 -shell 3 -solid 3 -t

cmakeperiodic rp -x 10 -y 10
checknbshapes rp -wire 20 -face 20 -shell 3 -solid 3 -t

savehistory h

explode b2 f
modified m2 h b2_2
cperiodictwins m2_twin m2

cmaterialson m2_pos + m2
cmaterialson m2_neg - m2_twin

if {![regexp "same shapes" [compare m2_pos b2]]} {
  puts "Error: incorrect material associations"
}

if {![regexp "same shapes" [compare m2_neg b1]]} {
  puts "Error: incorrect material associations"
}


crepeatshape r -x 1 -y 1
checknbshapes r -wire 76 -face 76 -shell 12 -solid 12 -t

savehistory h
generated g2 h b2_2
checknbshapes g2 -face 4 -t

cclearrepetitions r
checknbshapes r -wire 20 -face 20 -shell 3 -solid 3 -t

savehistory h

modified m2 h b2_2
cperiodictwins m2_twin m2

cmaterialson m2_pos + m2
cmaterialson m2_neg - m2_twin

if {![regexp "same shapes" [compare m2_pos b2]]} {
  puts "Error: incorrect material associations"
}

if {![regexp "same shapes" [compare m2_neg b1]]} {
  puts "Error: incorrect material associations"
}

crepeatshape r -y 1
checknbshapes r -wire 39 -face 39 -shell 6 -solid 6 -t

savehistory h

modified m2 h b2_2
cperiodictwins m2_twin m2

checknbshapes m2_twin -face 3 -t